/Engine/Source/Runtime/Engine/Classes/Materials/MaterialInstance.h
Sets new static parameter overrides on the instance and recompiles the static permutation resources if needed (can be forced with bForceRecompile). Can be passed either a minimal parameter set (overridden parameters only) or the entire set generated byGetStaticParameterValues(). Can also trigger recompile based on new set ofFMaterialInstanceBasePropertyOverrides
void UpdateStaticPermutation ( const [FStaticParameterSet](API\Runtime\Engine\FStaticParameterSet) & NewParameters, [FMaterialInstanceBasePropertyOverrides](API\Runtime\Engine\Materials\FMaterialInstanceBasePropertyOve-) & NewBasePropertyOverrides, const bool bForceStaticPermutationUpdate, [FMaterialUpdateContext](API\Runtime\Engine\FMaterialUpdateContext) * MaterialUpdateContext )